Combined switch and fuse



1939- w. o. SCHULTZ ET AL 2,176,227

COMBINED SWITCH AND FUSE Filed m 15, 1932 4 Sheets-Sheet 1 w. o. SCHULTZ ET AL COMBINED SWITCH AND FUSE Filed Julyl3, 1932 4 Sheets-Sheet 2 7 Z Z Z A \UF'I! 14111 H l m 1|.l4l m M I ll!!! M A l] 0 5 M, w J W 6 B 6 Z a H 5 Oct. 17, 1939.

w. o.- SCHULTZ- ET AL 2, 227

COMBINED SWITCH AND FUSE Filed July 15, 1952 4 Sheets-Shae}: 3

3nnentofs ct. 17, 1939. w. o. SCHULTZ ET AL 2 116 221 COMBINED SWITCH AND FUSE 3nnentor5 221 quomeg Patented Oct. 1-7, 1939 UNITED STATES PATENT OFFICE COMBINED SWITCH AND FUSE William O. Schultz, South Milwaukee, and Alwin G. Steinmayer, Milwaukee, Wis., assignors to Line Material Company, South Milwaukee, Wis., a corporation of Delaware Application July 13, 1932, Serial No. 622,292

36 Claims. (Cl. 200-114) This invention relates to a combined switch tion of a fuse link, the lower end of the fuse link and fuse, being clamped to an auxiliary pivoted member In fuse constructions as heretofore made for which pivotally supports the fuse, and which use in the protection of high voltage lines it has when the fuse link blows, permits the fuse to 5 been the practice heretofore to provide some drop downwardly, thereby detaching the upper 5 means in certain forms of these fuses for allowing end of the fuse and allowing the fuse structure the fuse to rock outwardly after the fuse link to swing outwardly, and to so construct the dehas been ruptured, to thereby increase the sepvice that a direct spring contact connection is aration between the live side of the line and the provided between the auxiliary pivoted member fuse structure, or link receiving member and the lower contact, 10

These devices have heretofore been made either a similar direct connection by means of a spring in the form of a stick type of circuit breaker, contact being provided between the upper conwhich requires a relatively large swing, or in tact of the fuse and the upper contact member, other types of fuses in which the fuse is located provi i n l ein m e f r h pr tion f within the tube open to the weather at the top. t pp and lower portions of the mechanism 15 In view of the fact that fiber is the usual, and, from the effects of sleet. in fact, a very highly serviceable material for the Further O j s are to prov de a novel form construction of the inner portion at least of fuse of combined se a d Switch which is Co p tubes, it has been found that devices of this nawhich is y to P which s reliable in D- ture collect water and the fiber, as is well known, r n, and wh h m y e rea y r -f 20 absorbs the water in considerable quantity causmoved p a ed, as O casion demands.

ing warping and other defects which renders the od ments of the invention are shown in fuse unserviceable and inoperative. the o panying drawing in which! This invention is designed to overcome t Figure 1 is a side elevation of one form of the above noted defects, and objects of this invention device. 25 are to provide a combined switch and fuse which Figure 2 is a View, Partly in Section, Of the is so made that although a fuse tube is used and Structure Shown in Figure is so constructed that it swings outwardly to Figure 3 iS a front V ew of the structure shown provide the maximum space between the live porin Figure tion of the line and the remainder of the fuse Figure 4 S a View, with parts broken away, 01 30 upon rupturing of the fuse link, nevertheless is a modified form of the inventionprotected from the collection of water within the Figure 5 is a View Of the 10We1' Portion of a e, tube, so that although a fiber tube or at least a Showing further o f the invention. fiber lined tube may be employed, nevertheless Figure 6 is VieW corresponding o Figure warping and distortion and other incident de- Showing e Still further m Of the invention. 35 fects due to the collection of water is wholly Referring to Figures 2 and it W111 be Seen a ided, that the fuse is carried from an upper terminal Further objects are to provide a fuse which is member and lower terminal member 2 so made that one end automatically moves tried by suitable insulators 3 from a base member 4,0 wardly a considerable distance from the live side It The fuse tube 5 is provided w t n upp 40 of the line and prevents leakage after the fuse Contact 5 and a 10Wer Contact fuse Strip link has ruptured, and which although it swings ceivihg ber T e members 6 and I are through a considerable arc, nevertheless is cushp d W fi t faces a t w ch the conioned at the lower portion of its swing so that extect p s 8 and 9 hear when the fuse is in its cessive forces or jars and excessive strains are Operative po i n, as Shown on the drawings- 45 not imposed upon the structure, and which also The member I is provided with a slotted poris so made that it may be readily re-fused and retion adapted to receive the free end. of the fuse placed and may be removed or repositioned by link l0, and is provided witha clamping screw or means of an ordinary fuse stick or switch stick, bolt II in the usual manner so as to permit the construction also providing an operating ring ready renewal of the fuse link. 50 or member adapted to be engaged by the fuse This construction is most clearly shown inFigstick when it is desired to use the device as a disure 2, from which it will be seen that the fuse connecting switch. link In extends downwardly through the fuse Further objects are to provide a fuse constructube around its bottom edge and is thereafter tion in which a fuse tube houses the major porclamped to the member 1, thereby constituting 55 the device an expulsion fuse. The fuse tube 5 is open at its lower end, and at its upper end is provided with the upper contact 6 closed by a removable screw threaded cap l2 provided with a projecting upper pin I3.

The fuse link i is provided with a reduced portion 14 adjacent its upper end and with a clip or disk l at its upper end adapted to be clamped between the cap l2 and the upper contact 6.

The upper contact member I carries a retaining member in the form of a sleet hood [6 pivoted, as indicated at H, to the upper terminal member. This sleet hood is provided with rearwardly projecting ears l8, see Figure 1, which form stops to arrest its downward motion. It is urged downwardly by means of a leaf spring IS.

The sleet hood or upper latching or retaining member is provided with a recess 20 which normally receives the projecting stem or pin I3 of the cap l2, as shown in Figures 1 and 2. The outer end of the combined upper latching member and sleet hood is provided with a flared portion 2|, as shown most clearly in Figure 3, to facilitate the entrance of the upper contact and the adjacent portions.

The upper contact 6 pivotally carries an operating ring or releasing member 22 which is spring urged into the position shown in Figure 1. This operating ring has a forked inner portion, thereby providing arms 23 located below the latching sleet hood or latching member, so that when the ring is pulled downwardly by a switch rod or switch hook, the arms 23 move upwardly and thereby release the' fuse and allow it to swing outwardly and downwardly about its pivoted lower end. This allows the device to be used as a disconnecting switch.

The lower member I is provided with trunnions or pivot portions 24 which fit within the spaced hooked arms 25 of the lower terminal member 2. The lower portion of the lower terminal member, which forms a continuation of the hooked arms 25, is continued downwardly, as indicated at 26, and it is preferable to have these arms slightly converge towards their inner ends, as indicated in Figure 3, so as to receive the tapered or wedgeshaped extensions 21 of the member I when the fuse swings downwardly through approximately 180 from its position shown in Figure 1.

This construction prevents an abrupt shock or blow from the relatively heavy swinging mass, but

instead cushions the device, as it provides a sliding wedge contact between the arms 26 and the wedge members 21. The members 26 as well as the arms 27 will slightly yield to enhance the cushioning action.

The hooked arms 25 are so formed that the trunnions or pivots 24 may be readily positioned or removed therefrom through the curved slot located between the extensions 28 and the arms 25, see Figure l.

The upper portion of the member! is bifurcated and has projecting ears or arms 29 located character 34.

The operation of the device is as follows! When an overload occurs, the fuse link ruptures at its reduced portion 14, see Figure 2, and blows the fuse link forcibly from the fuse tube 5, thereby releasing the member 'I or lower contact member which had been held tightly in place by the fuse link itself, as is apparent from an examination of Figure 2. The member 1 is now permitted to rock about its lower pivot pins 24 and also about the upper pivot pins 3|, thereby dropping the fuse downwardly a sufiicient distance to disengage the pin [3, see Figures 1 and 2, at the upper end of the fuse from the upper latch or sleet hood. This, therefore, disconnects the fuse from the upper contact and allows the fuse to bodily swing about its lower end through approximately 180. As previously stated, the fuse is cushioned at the lower end of its swing so that there is no severe shock imposed upon any of the parts.

It is to be noted also that the springs 8 and 9, see Figures 1 and 2, aid in the positive starting of the fuse after expulsion of the fuse link, as they press the fuse outwardly. This, therefore, materially aids in a positive action of the device.

It is apparent, therefore, that the fuse first operates as an expulsion fuse and thereby automatically releases itself and drops downwardly and swings completely away from the upper or live contact, giving maximum separation of the parts and preventing any possible chance of leakage or other disturbances of this type.

The fact that the fuse tube is closed at its upper end has the advantage that a distinct expulsion action occurs and has the further advantage that a distinct recoil of the fuse tube or fuse cartridge occurs. For instance, when a heavy short circuit occurs, the recoil tends to hold the fuse tube contacts tightly in engagement with the stationary contacts until the expulsive action of the fuse has cleared the circuit. By this time the effect of the recoil is over and the device drops open. On more limited overload conditions the recoil is not so severe, but nevertheless the device functions in exactly the same way as described above and insures just sufficient time delay to prevent breaking of the circuit at the contacts before the expulsive action has had sufficient time to clear the circuit. Under both conditions, the circuit is broken by a true expulsion action and the device is automatically held closed by this expulsion action until the circuit is cleared, thereby avoiding arcing at the contacts.

Further, in this particular form of the invention, the pivot point 3| is located upon the inner side of the tube and increases its distance of travel and the time delay before the contact at the upper end of the device is broken.

It is to be noted particularly that the expulsion fuse is open at its lower end so that water cannot collect in the fuse tube. It is securely closed at its upper end by the contact cap !2, see Figure 2, so that water cannot enter the upper end of the fuse.

It is thus possible to use a fiber or similarly lined tube with the assurance that the fiber will not be water soaked and consequently will not warp the structure out of shape and prevent its free and easy operation.

It is to be noted from Figure 2 that the fuse tube is lined with fiber, indicated by the reference The fuse tube, therefore, constitutes a composite structure with an exterior or outer portion formed of phenol condensate prodnot, commonly known as Bakelite or other suitable material, and an inner portion formed of fiber or similar material which resists the terrific heat generated by the are at the time the fuse melts.

Referring to Figure 4 wherein another form of the invention is disclosed, it will be seen that the fuse tube 35 carries an upper contact memberwhich the upper contact 36 of the fuse is normally positioned. Each of the arms 42 is provided with a latching spring 43 secured thereto and extending upwardly through an aperture in its corresponding arm, so that the inwardly turned portion 44 of the spring will act as a stop to limit its downward motion. The springs 43 normally engage lugs 45 integral with the upper contact 36 and thus retain the fuse in position.

However, the fuse may be readily released when it is to be used as a disconnecting switch by pulling downwardly on the operating ring 46,

such ring being connected to a pair of arms 41 which press the springs 43 upwardly and thus release the lugs 45, permitting the fuse to swing outwardly.

The lower-contact 3.1 is slotted and receives the free end of the fuse link 43, such fuse link being locked in place by means of the screw or bolt 49 in a manner corresponding to that previously described. v

The lower loop of the fuse link 43 passes around the rounded lower end of a latching lever 50, which is pivoted, as indicated at 5l', to the lower contact 31. This lever 50 bears against the free end of a bell crank lever 5| which is pivoted to the lower contact 31, as indicated at 52. This lever 5| is duplicated on opposite sides of the fuse and each of the levers 5| is provided with outwardly projecting trunnions or pivot pins 53 which seat within the slots 54 formed in the side plates 55. The side plates 55 are folded outwardly from the terminal member, as shown in Figure 4,'and are slightly outwardly spread corresponding to the arms 26 of the first form of the invention. They are thus inherently slightly yielding. However, they are urged towards each other by means of a small helical spring 56 surrounding a through bolt 51 to thus slightly reinforce such plates.

The plates 55 receive between them the tapered lugs 58 formed integrally with the lower contact member 31, and thus serve to cushion the final portion of the swing of the fuse and prevent jarring of the apparatus.

It is to benoted also that the lower end of the lugs 58 form abrupt shoulders against which the levers 5| bear when they are in their restrained position, as shown in Figure 4. The fuse is, therefore, prevented from moving downwardly under normal conditions, However, when the fuse blows; the lever 50 is no longer restrained by the fuse link and consequently it swings outwardly and allows the levers 5| to rock downwardly, thereby rocking the pivot points 52 outwardly and thus lowering the fuse. The. lugs 45 of the upper contact 36 are thus disengaged from the retaining or latching springs 43 and the fuse.

rocks outwardly and downwardly, as previously described.

Referring to Figure 5 wherein another form of the invention is disclosed, it will be seen that the fuse tube 59 is provided with a lower contact member '60 engaged and urged outwardly by means of a contact spring 6| carried by the lower terminal member 62. A pair of hooked supporting arms 63 project outwardly from the lower terminal member and receive the fulcrum pins or pivot pins 64 of a pair of bell crank levers 65. These bell crank levers are pivotally connected, as indicated at 66, to the lower contact member 60 and are provided with cam faces 61. I

The fuse link 63 is received by the fuse link receiving member 69 and locked by the screw or bolt III, as previously described. This member 69 is provided with a pair of lever arms 'I| pivoted, as indicated at 12, to the lower contact 6|! and provided with extensions 13 which engage the cam faces 61 of the lever 65.

A pair of outwardly projecting springs 14 are carried by the stationary arms 63 and are located on opposite sides of the lower end of the fuse. These springs act as cushion members and are adapted to be struck by'a transverse bar I5 carried by the fuse to thereby cushion the fuse and prevent excessive pressures being produced at the lower end of the swing of the fuse.

The contact spring 6| urges the fuse outwardly, but it is restrained by the lever mechanism corisisting of the bell crank lever 65 and 1|. However,- when the fuse blows, the member 69 rocks upwardly a slight distance, thereby releasing the levers 65 and allowing the fulcrum points 66, to move outwardly beyond the fulcrum points 64, thus allowing the fuse to drop downwardly and' release from its upper end. The fuse then swings outwardly, as previously described.

Referring to Figure 6 wherein a further form of the invention is shown, it will be seen that the fuse tube 16 is provided with a lower contact member I1 engaged by the flat portion 18 of a contact spring carried by the lower terminal member. A pair of outwardly projecting arms 19 are also caried by the lower terminal member and are provided with hooked ends 80 spaced a material distance below the lower edge of the main body of the members I9 to thus provide in effect a laterally opening, elongated slot within which the trunnion members or pivot pins 8| rigid with the'lower'contact 11 are carried. The fuse link 32 passes around the lower end of the fuse link receiving member or lever 33, which is pivoted, as indicated at 34, to the contact 11. It isprovided with a cam face 35 which engages the free end of a lever 36 and holds such lever against a stop 81 carried by the member I1.

The lever 36 is provided with an extension 33 which carries a transverse bar 39. The bar, 39. rests upon the slanting upper faces 90 of the member I9 and thus supports the fuse in the position shown. 6

However, when the fuse blows, the fuse link 32 releases the lever 33 and allows the lever 36 to rock aboutits-pivot 9| in a clockwise direction,

thus allowing the fuse to drop downwardly until the trunnions 8| or pivot pins rest upon the books 33. The spring 18. forces the fuse downwardly and outwardly and this spring, cooperating with the upper spring not shown but of a manner, as by having the fuse tube 16 strike against a transverse pin 92 carried by the member 19, orin fact cushioned or arrested in any manner desired, for example in a manner similar to any previously described.

It is to be noted also that the downwardly and outwardly inclined upper faces 90 of the member 19 urge the fuse outwardly as it drops downwardly. The lower portion of the transverse bar 88 is rounded and somewhat of a rolling action takes place between this member and the upper faces 90 of the outwardly projecting arms 19.

It will be seen that in all types of the invention that the expulsion fuse automatically releases itself when the fuse link is ruptured and allows the fuse to drop downwardly, thus disengaging itself from the upper catch and subsequently swinging outwardly to provide maximum separation between the upper end of the fuse and the upper contact.

It will be seen further that a very simple type of combined fuse and disconnecting switch has been provided which is automatic in its action, which is adapted for outdoor use, which prevents the accumulation or retention of water within the fuse tube, and which is thoroughly reliable in its operation.

It is to be distinctly understoo that any of the several types of fuses may be provided with a projecting lip similar to the lip 33 of Figure 1, so that such lip may be received by a fuse stick or pole inthe usual manner, and that other combinations, not specifically illustrated, may be employed. Therefore, although this invention has been described in considerable detail, it is to be.

restrained from movement by said fuse link, said means holding said fuse in place and adapted to first lower said fuse when said fuse link is fused, to disengage said fuse from said upper terminal member, said fuse thereafter pivoting about its lower portion and swinging away from said upper terminal member.

2. A fuse assembly comprising upper and lower terminal members, a fuse having upper and lower contacts electrically connected to said terminal members, a fuse link carried by said fuse, lever mechanism for bodily lowering said fuse out of engagement with said upper terminal member, said lever mechanism normally holding said fuse in an elevated position and being normally held against movement by said fuse link, said fusebeing pivotally supported adjacent its lower end and adapted to swing outwardly when disengaged from said upper terminal member.

3. A fuse assembly comprising upper and lower terminal members, a fuse having upper and lower contacts electrically connected to said terminal members, a fuse link carried bysaid fuse, lever mechanism for bodily lowering said fuse out of engagement with said upper terminal member,

said lever mechanism normally holding said fuse from said upper terminal member, and manually operable means for disengaging said fuse from said upper terminal member.

4- A fuse construction comprising upper and lower terminal members, a fuse having upper and lower contacts electrically connected to said terminal members, a fuse link carried by said fuse, lever mechanism for bodily lowering said fuse out of engagement with said'upper terminal member, said lever mechanism normally holding said fuse in an elevated position and being normally held against movement by said fuse link, said fuse being pivotally supported adjacent its lower end and adapted to swing outwardly when disengaged from said upper terminal member, and manually operable means independent of said lever mechanism for disengaging said fuse from said upper terminal member.

5. A fuse construction comprising upper and lower terminal members, a fuse having a tubular body portion, said fuse being normally latched to said upper terminal member and pivotally supported from said lower terminal member, said fuse having an open lower end, a fuse link within said tubular body portion and extendingv through the lower end of said body portion, and mechanism controlled by the tension of said fuse link for unlatching the upper portion of said fuse from said upper terminal member when said fuse blows, said mechanism contacting with the lower portion of said fuse link.

6. A fuse construction comprising upper and lower terminal members, a fuse having a tubular body portion, said fuse being normally latched to said upper terminal member and pivotally supported from said lower terminal member, said fuse having an open lower end, a fuse link within said tubular body portion and extending through the lower end of said body portion, and mechanism controlled by the continuity of said fuse link for uniatching the upper portion of said fuse from said upper terminal member when said fuse blows, the lower part of said fuse link extending over a portion of said mechanism.

7. An expulsion fuse assembly comprising upper and lower terminal members, a fuse latched to said upper terminal member and pivoted to said lower terminal member, said fuse having a tubular body portion closed-at its upper end and open at its lower end, a fuse link within said tubular body portion, and means mechanically controlled by the tension of said fuse link for uniatching the upper portion when said fuse blows.

8. An expulsion fuse assembly comprising upper and lower terminal members, a fuse detachably secured to said upper terminal member and pivoted to said lower terminal member, saidfuse having av tubular body portion closed at its upper end and open at its lower end, a fuse link within said tubular body portion extending outwardly from the open lower end of said tubular body portion, and means mechanically controlled by the lower projecting portion of said fuse link for detaching said fuse from said upper terminal member. q

9. An expulsion fuse assembly comprising upper and lower terminal members. a fuse detachably attached to said upper terminal member and pivotally supported from said lower terminal member, said fuse having a tubular body portion closed at its upper end and open at its lower end and provided with upper and lower contacts, upper and lower contact springs electrically connecting said upper and lower terminal members and said upper and lower contacts respectively,

a fuse link carried within said tubular body portion and electrically joining said upper and lower contacts and projecting from the lower end of said tubular body portion, and mechanism controlled by the lower projecting portion of said fuse link for detaching said fuse from said .upper terminal member when said fuse blows,

whereby said fuse rocks outwardly and downwardly from said upper terminal member when said fuse blows.

10. An expulsion fuse assembly comprising upper and lower terminal members, a fuse latched to said upper terminal member and pivoted to said lower terminal member, said fuse having a tubular body portion closed at its upper end and open at its lower end, a fuse link within said tubular body portion, and means controlled by said fuse link for holding the fuse in latched position due to the recoil of the fuse during expulsion and for unlatching the upper portion after the expulsive action has ceased.

11. An expulsion fuse assembly comprising up per and lower terminal members, a fuse latched to said upper terminal member and pivoted to said lower terminal member, said fuse having a tubular body portion closed at its upper end and open at its lower end, a fuse link within said tubular body portion, and downwardly and outwardly rocking lever mechanism controlled by said fuse link for holding the fuse in latched position due to the recoil of the fuse during expulsion and for unlatching the upper portion after the expulsive action has ceased.

12. An expulsion fus e assembly comprising upper and lower terminal members, a fuse latched to said upper terminal member, said fuse having a tubular body portion closed at the top and open at the bottom, a fuse link within said tubular body portion and extending outwardly through the lower open end thereof, said lower terminal member constituting a pivot support, a lever pivoted adjacent its upper end to said body portion and pivotally resting in the pivot support of said lower terminal member and normally approximately paralleling said body portion, the lower end of said link extending over the lower end of said lever and normally holding said lever in place, and means carried by said lever for clamping said link to said lever.

13. A fuse switch comprising upper and lower line terminals, a spring extension from one of said terminals, bearings associated with the other terminal, a cartridge having terminal engaging elements, one of which is adapted to springingly cooperate with said spring extension and the other with said bearings and which latter element is movably related to the cartridge, a fuse link associated with the cartridge and means whereby said link when in normal connected position, holds said movable terminal so as to effectuate tensioning of the said spring extension when the cartridge is closed and releases the said movable terminal when the fuse blows, the -articulation between the said movable terminal and the cartridge being such as to release the upper terminal engaging element from the spring extension when said fuse blows.

14. A fuse switc comprising upper and lower line terminals, a spring holding means extending from one of said terminals, bearing means associated with the other terminal at a predetermined distance from said holding means, a cartridge having terminal engaging elements,

one of which is fixed and adapted to springingly cooperate with said spring extension and the other with said bearing means and which latter element is movably related to the cartridge, a fuse link associated with the cartridge and means whereby said link when in normal connected position holds said movable terminal so asto be separated from the fixed terminal a distance greater than said predetermined distance, and the articulation between the said movable terminal and the cartridge being such as to shorten said distance and release the upper terminal engaging element from the said extension when said fuse blows.

15. A fuse switch comprising upper and lower line terminals, one of said terminals having a spring extension, bearing means associated with the other terminal, a cartridge having terminal engaging elements, one of which is adapted to springingly cooperate with said spring extension, the other of which is movably related to the cartridge, a fuse link associated with the cartridge and means whereby said link when in normal connected position holds said movable terminal so as to effectuate tensioning of the said extension when the cartridge is closed and releases the said movable terminal when the fuse blows, the articulation between the said movable terminal and the cartridge being such as to release the upper terminal engaging element from the said tension when said fuse blows, said movable contact being gudgeoned in said bearing means whereby after said fuse has blown, the cartridge may rotate to clear the untensioned extension.

16. A fuse switch comprising upper and lower line terminals, a spring extension from one terminal, a bearing support associated with the other terminal, a fuse cartridge including a tube and terminal engaging elements, one of which engaging elements is adapted to cooperate with said extension, the other of which is pivoted to the cartridge, said pivoted engaging element having gudgeons cooperating with said bearing supports, and a fuse adapted when normally attached to said terminal engaging elements to hold the movable terminal engaging element against the tube to stiffen the cartridge whereby the same may be sprung into line closing position.

17. A fuse switch comprising upper and lower line terminals, a spring extension from one terminal, a bearing support associated with the other terminal, a fuse cartridge including a tube and terminal engaging elements, one of which engaging elements is adapted to cooperate with said extension, the other of which is pivoted to the cartridge, said pivoted engaging element having gudgeons cooperating with said bearing supports, and a fuse adapted when normally attached to said terminal engaging elements to hold the movable terminal engaging element against the tube to stiffen the cartridge whereby the same may be sprung into line closing position, the movable engaging element pivoting on the tube to cause collapse of the cartridge when said fuse blowsj 18. A fuse switch comprising line terminals, a spring extension from one terminal having a reaction point, a bearing support associated with the other terminal, a fuse cartridge including terminal engaging elements, one of which is rigid and adapted to cooperate with said extension at said reaction point, the other of which is pivoted .to the cartridge, said pivoted engaging element having gudgeons cooperating with said bearing supports, and a fuse adapted when normally attached to said terminal engaging elements to hold the movable terminal engaging element so that the cartridge may be sprung into line closing position, the said gudgeons, pivot point and reaction point being almost aligned when the fuse is connected.

19. A fuse switch comprising line terminals, a spring extension from one terminal, a bearing support associated with the other terminal, a fuse cartridge including terminal engaging elements, one of which is rigid and adapted to cooperate with said extension, the other of which is pivoted to the cartridge, said pivoted engaging element having gudgeons cooperating with said bearing supports, and a fuse adapted when normally at tached to said terminal engaging elements to hold the movable engaging elements rigidly with respect to the cartridge so that the cartridge may be sprung into line closing position to tension the extension, and adapted by fusing to release the movable terminal engaging elements to effect collapse of the cartridge from the said extension.

20. A fuse switch comprising upper and lower line terminals, a spring extension from one terminal, a bearing support associated with the other terminal, a fuse cartridge including terminal engaging elements, one of which is rigid and adapted to cooperate with said extension, the other of which is pivoted to the cartridge, said pivoted engaging element having means cooperating with said bearing supports, and a fuse adapted when normally attached to said terminal engaging elements to hold the movable terminal engaging element so that the cartridge may be sprung into line closing position to tension the extension, and adapted by fusing to release the movable terminal engaging elements to effect collapse of the cartridge from the said extension, the cartridge being adapted subsequently to rotate forwardly and clear the upper terminal extension.

21. In a fuse switch embodying spaced line terminals, a tubular fuse holder, a fuse link in said holder held at one end against endwise movement relative to said holder, a lever carried by said holder engaging the opposite end of said fuse link, cooperable means on said lever and one of said line terminals providing a hinged mounting for said fuse holder, the other of said line terminals being resilient and adapted to exert an endwise force on said fuse holder.

22. A fuse unit comprising in combination a tube, a terminal closing the upper end of the tube and providing at its upper end a shoulder whereby the upper end of the tube may be held against lateral motion, a metallic member secured to the tube adjacent its lower end, a supporting link secured pivotally to the metallic member, a fuse link in the tube connected at its upper end to said terminal, and by anchorage of its lower end controlling the angular position of the supporting link With-respect to the tube, said supporting link having laterally spaced rotary bearing portions for cooperation with spaced stationary bearings to provide stable rotary support.

23. A fuse unit comprising in combination a tube, a terminal closing the upper end of the tube and providing at its upper end a shoulder whereby the upper end of the tube may be held against lateral motion, a metallic member secured to the tube adjacent its lower end and having a bracket arm extending laterally with respect to the tube, a bell crank lever having one arm pivotally connected tosaid bracket arm and having a free arm, said bell crank lever having laterally spaced bearing members forming a rotary support for the bell crank, a fusible link in the tube electrically connecting said terminal and said bell crank and mechanically restraining the free arm of said bell crank.

24. In a cutout switch having spaced terminals, a tube, a contact on the tube engaging one of the terminals, a second contact onsaid tube pivotally supporting the tube from the other of said terminals, said second contact including a lever having a pin joint connection with the tube and a pivotal connection with the last mentioned terminal to provide a two-joint pivot, and means for holding said lever against pivotal movement relative to said tube and for establishing an arc in said tube, said means including a tensioned fuse link establishing a circuit through said tube.

25. In a cutout switch having spaced terminals, a tube, a contact on the tube engaging one of said terminals, a second contact on said tube pivotally supporting the tube from the other of said terminals, said tube beingbodily movable relative to said pivot for withdrawing the first mentioned contact from engagement with said one terminal, and means for holding said tube against movement relative to said pivot for drawing an arc in said tube, said means including a tensioned fuse for establishing a circuit through said tube.

26. In a disconnecting switch having spaced terminals, a tube having at one end an upper contact latched to one of said terminals, and having at the other end a lower contact pivoted on the other of said terminals, said last mentioned end being movable relative to said pivot thereby to withdraw the upper contact from the latch, and a flexible conductor in said tube connecting said contacts and holding said tube against movement relative to said pivot, said conductor including a separable portion.

27. A fuse unit comprising in combination a tube, a terminal closing the upper end of the tube and providing a shoulder whereby the upper end of the tube may be held against lateral motion, a metallic member secured to the tube adjacent its lower end, a substantially straight supporting link secured at its upper end pivotally to the metallic member and adapted to lie substantially parallel with the tube, a pair of trun-' nions extending from the opposite sides of said link for cooperation with spaced stationary bearings, and a fuse link inthe tube connected at its upper end to said terminal, and its lower end connected to the lower end of sai supporting link to hold the same substantially parallel with the tube, melting of the fusible link freeing the supporting link for angular motion about its pivot on the metallic member.

28. A fuse cartridge including a tube having terminal elements, one of which is rigid, and has a projection serving as a catch, the other element having pivotal connection With the tube, and having laterally spaced oppositely extending gudgeons to provide rotary support, and a fuse adapted when normally attached to said terminal elements to hold the movable terminal element rigid with respect to the tube thereby disposing the catch, pivotal connection, and the gudgeons almost in alignment.

29. In combination, an upper line terminal, a lower line terminal, a fuse tube adapted to be closed at its upper end, a coupling between the upper line terminal and the upper end of the fuse tube, comprising a latch preventing the upper end of the tube from swinging out of engagement therewith but allowing endwise disengagement of the tube, a coupling between the lower end of the tube and the lower line terminal providing for free pivotal motion of the tube on said lower terminal when the upper coupling is disengaged, and comprising guiding means allowing for end- Wise sliding of the tube relative to the lower line terminal to cause disengagement of the upper coupling, and means including a fusible link in the tube for holding the tube against endwise sliding movement relative to the lower line terminal.

30. In combination, a pair of line terminals, one above the other, a fuse tube haying coupling devices for connecting it to the line terminals, said tube being movable endwise and pivotally with respect to the lower terminal, one of said terminals having spring means for thrusting the tube down endwise, a tension element comprising a fusible link in the tube for electrically con-= necting said coupling devices, one of said devices having means restrained by the tension element controlling the endwise position of the tube, said tube being guided for longitudinal motion of translation to cause disconnection of the upper coupling device.

31. An expulsion fuse assembly comprising upper and lower terminal members, a latch mounted on the upper terminal member, a fuse held by said latch to said upper terminal member and pivoted to said lower terminal member, said fuse having a tubular body portion closed at its upper end and open at its lower end, a fuse link within said tubular body portion, and means mechanically controlled by the tension of said fuse link for releasing the upper portion from said latch when said fuse blows.

32. In a circuit breaker, an expulsion tube of insulating material spaced conducting means fixedly attached on said tube, insulated supporting means for said tube, latch means on one of said insulated supporting means for engaging the conducting means at one end of said tube, two spaced pivots at the other end of said tube about which the tube may pivot to open circuit position, a member connecting said pivots, means locking said tube and member for movement as a unit into closed circuit position and operable on overload to cause circuit opening within the tube and to release said locking engagement.

33. In a circuit breaker, an expulsion tube of insulating material, conducting means fixedly attached on the tube, insulated supporting means for said tube, latch means on one of saidinsulated supporting means for engaging the conducting means at one end of said tube, plural pivot means associated with the conducting means at the other end of said tube for pivotally mounting said tube upon the other of said insulated supporting means, link means connecting said pivot means, and means to maintain said link means in fixed relation to said tube during closing movement of said tube but operable by an overload current to disestablish said fixed relation and to cause circuit opening within said tube.

34. An expulsion fuse assembly comprising upper and lower terminal members, a fuse latched to said upper terminal member, said fuse having a tubular body portion closed at its upper end and open at its lower end, a fuse link within said tubular body portion and means movable as an incident to the blowing of the fuse link to effect unlatching of the upper portion when the fuse blows.

35. In combination, a stationary contact terminal, a drop out fuse including a closed top tube engageable therewith, a latch for latching the drop out fuse to said contact terminal, and a spring operable upon blowing of the fuse to release said latch and extend the are.

36. In a drop out fuse assembly, a stationary contact, a pivoted fuse having an open lower end and a cap at the upper end, a stationary contact for engaging said cap, said tube being provided with a ferrule at its lower end, and a pivoted mounting to permit the tube to swing outwardly and downwardly to disconnect said cap from said stationary contact when the fuse link melts, and a resiliently stressed fuse link operating to interrupt current flow through the device before the cap leaves engagement with the stationary contact whereby arcing between the stationary contact and the cap is avoided.

WILLIAM O. SCHULTZ. ALWIN G. STEINMAYER. 

